JSON MarshallableDocument Raw function

[juagargi]

If an object is created programmatically (e.g. with a call to NewPolicyCertificate() to create a Policy), the JSONField is not set accordingly. Then if a call to Raw() is done, nothing is returned.
Same applies when a field of the object is changed.
Make the object read-only and cache the JSON in a variable, or make Raw() to always derive the JSON at call time.